


Sinon's Treasure

by ReinesYatogami647



Category: Sword Art Online (Anime & Manga)
Genre: F/F, F/M, Family Feels, Protective Siblings, Sibling Bonding, Team as Family
Language: English
Status: Completed
Published: 2020-03-26
Updated: 2020-03-26
Packaged: 2021-02-28 22:55:31
Rating: General Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 4,225
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/23325100
Author URL: https://archiveofourown.org/users/ReinesYatogami647/pseuds/ReinesYatogami647
Summary: Sinon, Asuna, Leafa, Lisbeth and Silica went on a newly discovered dungeon on the 22nd Floor of New Aincrad.
Relationships: Asada Shino | Sinon/Original Female Character(s), Kirigaya Kazuto | Kirito/Yuuki Asuna | Asuna
Kudos: 6





	Sinon's Treasure

**Author's Note:**

> Overview:  
> Type: Romance (?) and Friendship  
> Anime: Sword Art Online  
> Shipping (for romance): Kirito x Asuna (slight) and Sinon x OC (a bit romantically, I guess? Idk)
> 
> Note: WOOHH SINON BEST GRIL!!  
> Sinon: ?  
> Me: GAAAHHH SINON-SAN! I was-?!

"Shinonon! Behind you!!" Asuna yelled to Sinon. She was busy healing them to join them in battle. Rather, Leafa was joining them while she stayed behind, healing their party the best she could.

"Understood!" Sinon quickly recoiled, backflipping away from danger and shooting a barrage of white arrows to the goblin that they were battling. She defeated the goblin and they all kept running further into the dungeon.

"Review me on the background of this dungeon, Silica." Lisbeth says as she drinks a health potion while running. Silica nods and looks on her neck which hung a necklace.

"This dungeon isn't in the Old Aincrad in the Old SAO. Probably a newly added dungeon on the recent patch of ALO for New Aincrad. This dungeon has various floors and rooms that makes it a maze. Though, each room of the dungeon is filled with monsters with many drops if you are lucky to kill them with the hidden requirement to do so. You can defeat the monsters without using the requirements but you won't get the great monster drops if not. What makes these requirements unique is that you do not know them. But once you fulfill them, they'll show up on the upper right corner of your view and you'll get the monster drop as a reward of completing them. Anyway, back to the rooms, the rooms has various monsters to kill and you cannot proceed to the next room until you kill every single one in the room. At the end of this dungeon, you'll face a boss guarding a treasure not defined on the quest of the dungeon itself. So, questers will just have to defeat the final boss on the end of the dungeon to get this undefined treasure. Did I get the information right, Sinon-san?" Silica asked Sinon who was running a bit ahead of their party.

Sinon looked back and smiled then nods then continued running.

"Well...I hope that the treasure will be a legendary weapon, don't you?" Leafa smiles as she imagines herself wielding a katana that's colored gold.

"Ne, Shinonon! What do you think the treasure would be?" Asuna asks the archer Cat Sith excitedly and Sinon looks back at them and shakes her head. She hasn't spoken since entering the dungeon because she was too busy analyzing their current situation. They are in a Hidden Dungeon that can only be accessed by an Event Map and a Special Necklace that comes with it. One time, Sinon was looking at potions and she came across a mysterious merchant who gave her a map of this dungeon they were exploring in and with it, came a necklace that Silica was wearing right now. Sinon, even if she denied that she doesn't know what treasure would it be, still thought that there are some possibilities of what treasures it may be...and that's what she's thinking about.

_Leafa may be right and the treasure might be a legendary weapon. But who the heck will sell two items that lead to a legendary weapon? That possibility is completely ruled out._

_Next, there's the possibility that the final boss of the dungeon is the treasure itself. Rather, the final boss' monster drop. Rare monster drop. But it said on the Quest Info that came with the necklace and map that you're gonna need the necklace to track down the treasure and that the Final Boss of this dungeon drops many coins...but it isn't the real treasure.... So that rules that possibility out..._

_If it isn't the boss' rare monster drop, nor is it a legendary weapon, what is it?_

"Ne, Sinon, are you okay? You've been talking less since we entered this dungeon..." Liz had noticed it and the others stare at Sinon

Sinon smiles at them and gives them a thumbs up as they enter a new room "I'm fine. I'm just also thinking of what kind of treasure rewards would we get after this...anyway, let's prepare. Switch roles like earlier, Leafa, Asuna." Sinon orders as she is the leader of this party.

"Alright, Sinon-taichou!" Leafa cheerfully said as she recoiled and sheathed her katana, while Asuna got into vanguard, kept her wand and got her rapier. Soon, the room was filled with-

"What the- Horcs! They are known to have major magic resistance but higher sword skill weakness. Let's use that to our advantage, everyone!" Sinon orders as her party smirks and charges.

***

  
They've gotten a couple of floors higher but they are still good to go! And they also feel like they still have a long way to go. But anyway, they received many equipment and EXP points.

Silica finished off a group of fly-cat sith trap monsters and got a three star weapon and a three star cape after the battle. She immediately equipped it and was happy to have powerful grade gear on her.

Lisbeth leveled and was able to finish of a huge boar that could stand on its hind legs and was holding on an axe as a weapon all on her own and was able to get a mace with enhanced sword skill damage and various rare materials for new weapons for her blacksmith shop. Shockingly, there were many materials that could be handy for a blacksmith that came from this particular boar.

Leafa finished off a huge group of golems that ambushed her and got accessories that increases your resistance to various sword skills.

Asuna got some materials that could be used for her cooking back in their log cabin. Though she didn't get much, she was still thrilled at what she could make with them.

They were able to work together and kill the boss monster of that room. A giant Lizardman with armor...

Sinon leveled and smiled. But she received something other than EXP points. She received a map from the monster drop. A map that seemed...

"Ne, Liz, can I get the map for a sec?"

"Sure! What did you find, Sinon?"

"I may be wrong but...we may be running around in circles all this time...maybe the hidden requirement for advancing is to kill a certain number of monsters and get this thing...." Sinon tried to look for where the map she found could be put on the sides of their current map. Finally, she found a drawing with a stairs and three stars on it...but the full drawing was cut off. She nodded to herself and put the new map next to it. Magically, the two maps fixed itself and Sinon could see clearly where the boss was. Finally, she saw a notification from her view;

**Map Completer Phase 1**  
**Requirements to Unlock:**  
**1\. Kill 100 monsters**  
**2\. Find and kill the Red Lizardman**  
**~COMPLETED~**

**Map Completer Phase 2**  
**Requirements for Completion:**  
**1\. Red Lizardman killed with five attacks from five different weapons**  
**2\. Find the Map of Diversion Arch Castle part 1**  
**3\. Receive the necklace from automatic trading with NPC**  
**4\. Find the Map of Diversion Arch Castle part 2**  
**5\. COMPLETE the MAP**  
**~COMPLETED~**

**Congratulations Team Sinon**

"Did you guys...see the same thing?" Sinon asks her team and the other girls nodded "We...huh? What's...automatic trading, Sinon?" Leafa asks and Sinon thought hard "Oh! That may be it! The one who passed me the necklace offered a map along with it in exchange for a rare metal from the Spriggan Lands Kirito gave me...it couldn't be sold at a very high price and couldn't even make a decent weapon out of it. The information on the metal did say that it may be used for something by chance...and...I think the one who traded me that necklace and map was...in fact, a part of the current Dev Team of ALO..." Sinon said and everyone's eyes widened.

"Man...maybe this dungeon was made for you, Sinon. Maybe...the treasure at the end of it may be only for you...I mean, you went through many things to get here...." Silica says and Lisbeth smiles "I'd have to agree on Silica on this one, Sinon!" Sinon blushed "W-Well...why don't we go on?" she said, robotically exiting the room, her friends trotting behind her while giggling.

***

  
Reaching a wide room with troves of treasure like the one they encountered during the Norse Myth 'event', they looked around, readying her weapons. Suddenly, a warning appeared on their visors.

**Warning Boss Room**

**Treasure 30 meters away**

They looked around

"Look!" Leafa exclaims, pointing to a direction. Right there, was a cylindrical apparatus filled with green liquid. Inside, was...honestly, you could barely make what was inside. The liquid looked so thick that simply looking in a distance is not enough.

"Advance. But be careful." Sinon ordered and her team nods walking towards the apparatus. When they were close, a voice boomed across the room.

"If you touch the King's treasure, prepare for consequences." a deep voice said which made them all look around, trying to find its source.

"What...do you mean by consequences...?" Sinon said, courage evident on her voice. The deep voice laughed a little as suddenly, deep footsteps reverberated throughout the room. They felt like they were being look down upon...when Asuna turned, her eyes widened.

"The Gleam Eyes!? No, wait!" she exclaimed as everyone turned as well. Lisbeth and Silica gulped, recognizing the familiar SAO Boss Monster as it growled and lifted its huge sword...

"Everybody! Dodge it!" Asuna ordered as everyone followed "What IS THAT!?" Leafa exclaims "It's a different monster from the one in SAO...but the resemblance is uncanny.... That's the monster we fought where Kirito-kun showed his twin-blade technique." Asuna answered

"What!? What is a SAO monster doing in ALO!? I thought they recreated a different set of monsters for this New Aincrad?!" Sinon asked as she aimed for the monster's eyes, they saw the monster's name;

"Shadow of Oblivion. What a menacingly sounding name...." Lisbeth said as she used her mace to strike the monster's blue foot, which did something but wasn't enough.

"I guess we have to defeat this monster first if we want to get the treasure..." Silica said as she used her dagger to slash the monster's thigh multiple times, Pina using magic to harm it.

"Alright, then...let me use the technique Yuuki entrusted me with..." Asuna said as she retracted her wand and grabbed onto her rapier "That's a great idea, Asuna. Everyone! Lower its health a bit more so that Asuna could deal the finishing blow!" Sinon ordered and everyone nodded

Simultaneously, Lisbeth, Leafa, Silica and Sinon kept attacking the Shadow with sword skills. The Shadow was getting pissed off as Asuna waited for her chance. When it presented itself, the monster crouched down, having been weakened by 3 out of 5 health bars.

"Now!" Sinon yelled to Asuna as she launched her final arrow to decrease the monster's health a bit more...

"Alright..." Asuna's sword glowed and she launched towards the monster, using her 11-hit combo attack entrusted to her by Yuuki, Mother's Rosario.

After the attack everyone's eyes widened, the monster, as if powered up by some skill for it to endure a hit, stood up and lifted its sword to try to attack Asuna.

"ASUNA!!" Sinon yelled as she infused more power into her arrow and launched it onto the middle of the monster's face, in between its eyes. The monster groaned...it was then they noticed a red gem on the monster's face...

"A weak spot!" Sinon said as she fired repeatedly on that one spot. And finally, the monster growled one last time and vanished into bits of data...

Sinon sighed as she collapsed on the floor, the lights of the room turning on as window appeared in front of Sinon

_A last attack monster drop?_

"Nice job, Shinonon!!" Asuna praised as she hugged the Cat Sith archer. But the latter was emotionless. Sinon sighed and brought out the last attack monster drop...

"What...is that?" Leafa asked as she crouched down and stared at the item that Sinon was holding. Suddenly, a green light from that item pointed towards the necklace that Silica was wearing. It was then that they noticed that there was a small hollow on the necklace...shaped like the monster drop.

Sinon nodded to Silica who understood and handed her the necklace. Gently, Sinon placed the item onto the hollow and watched as the necklace gleamed and the pure green light emerged again and pointed to the earlier cylindrical apparatus with green liquid.

"That must be the treasure..." Silica said and Sinon nodded and headed towards it. Her party members followed her as she held the necklace onto the apparatus. Suddenly, the green liquid was drained from the apparatus, being replaced by a clear one. It was then that they saw the contents of the apparatus...

"Shinonon!?" Asuna exclaimed as they saw...someone was inside the apparatus. It looked like Sinon in the real world. She was curled up into a ball, naked and her short black hair flowing inside the apparatus. Sinon's eyes widened as she touched the apparatus. The window of the apparatus opened and it showed what its name was. It made everyone's eyes widen

**Asada Izumi**

Sinon gulped and touched the "Item Description"

**An AI designed by a doctor after a patient who played ALO. Though, not necessarily an actual AI, it was more specifically a player account that was frozen into this place to keep her alive...even in the real world.**

Sinon dropped down low and stared evenly on the girl inside the apparatus. Her friends observed her as she once again touched the apparatus.

**This treasure cannot be moved from here. Though, a path can now be created to it without going through the dungeon because you have finished the quest, Sinon Asada.**

The System message said this. Sinon's eyes widened. Her name...the system knew her name!?

***

"What do you want me to search for again, Sinon?" Kirito asked her. Right now, all of them were in Agil's shop in the real world. They all gathered there in order to talk about the girls' current quest.

Shino Asada gulped

"Search for Asada Izumi."

Kirito raised an eyebrow but Asuna elbowed his side "Just do it, Kirito-kun!" the Black Swordsman just nodded and searched for the name.

"Oh, found it. Let me read it..."

_Asada Izumi_

_A child from the Asada family who played AlfHeim Online (ALO) and was well-known for being a solo player. Everyone found her to be mysterious according to some people from the said game. Her Avatar name, for those who doesn't recognize her, is Asukara._

_But that was only because limited people knew her story._

_After being diagnosed of an unknown sickness, she - that is, her real world self - was confined in a hospital. Upon her request to keep being in the game even though she couldn't play anymore, she was put in the recent patch of the game as some sort of asleep AI._

_Nobody has ever found where exactly the body of Asukara was confined in. The Dev team of AlfHeim wouldn't speak of where it was. Only responding with;_

_"The right person will receive the right to see Izumi - that is, Asukara. We will not disclose any information beyond that."_

_Our team then concluded that the access to where the body of Asukara is confined in will only be given as some sort of "Event Item" to a certain specific player in the virtual world of AlfHeim._

"...that's what it says." Kirito said as he scanned the webpage a bit more.

Shino's eyes turned downcast as Agil served her latté to calm her nerves "It's on the house, kid. Take it and calm down." Shino thanked the man and took a sip of the beverage.

"Hey, wait. I found out what hospital Asukara is confined in!" Kirito suddenly said and everyone's eyes turned to him "Asuna, do you remember the hospital where Yuuki was confined in? You know, the one who has the technology for the Medicuboid?" Kirito asked and Asuna's eyes widened. She smiled at Sinon

"We may get to see Asukara soon, Shinonon!"

Shino's eyes widened

***

"Excuse me, we're looking for Asada Izumi." Asuna said to the reception as Shino trailed behind her. The receptionist looks at them "Can I have your name please?" she asked suspiciously

"Yuuki Asuna and Asada Shino."

The receptionist froze on typing. She looked up again to the two of them, her eyes landing suddenly on Shino

"Asada...Shino?"

"Yes."

The receptionist stood up "Please w-wait a moment. I shall call the doctor for you." she said then left

After a few minutes, a doctor came and Asuna recognized him as the one who helped her with Yuuki. "Yuuki-san! It's nice to see you again!"

"It's nice to see you too, Doc. This is my friend," Shino bowed "Asada Shino." the doctor paused for a moment then smiled at Shino. He gestured the two of them to follow him. The two females look at each other but followed the doctor anyway.

***

"Wha..."

Shino couldn't help but gape. The female laying down on the bed resembled her in almost every way. Only difference, her hair was now longer and wasn't tied like Shino's. She wore a Nerve Gear on her head. As some tubes was connected on her head and some electrons were plugged on her body.

Shino, Asuna and the Doctor neared the child who looked like Shino.

"You know, before she froze herself inside ALO, she said something to me. I asked her something because her request to be frozen in-game was unreasonable...but when she answered me why would she want to be inside the game even if she is sick..." the Doctor speaks as both females look at him

"You know what she answered?"

"What, Doctor?" Shino asked

The Doctor's face looked so in thought, as if he was relishing a distant memory...

_"The entire reason why I started playing ALO wasn't to be 'in' I don't care if I don't keep up with latest technology, Doc. The true reason is that I'm looking for distant sibling..."_

_"What? You have a sibling?"_

_"I don't know if she is my sibling or whatever. I heard what happened to her. How her new friend rescued her from being killed.... I wanted to be there for her and help her too. But...I didn't even know where she exactly is. But when I heard she started playing this fantasy game called "AlfHeim Online", I wanted to take the chance to look for her..."_

_"You want to look for her? Do you even know her name?"_

_"Well, her in-game Avatar name yes. Her name is..."_

"...Sinon." the Doctor said as Shino's eyes widened as she looked onto the sleeping female on the hospital bed

"I have a contact named Kikuoka-san. He said that it is true that there is someone playing ALO who converted from another game named as Sinon. He told me that her real name is Shino Asada. It was then that I confirmed that you ARE the one she was looking for." the Doctor said as Shino bent down to touch the girl's hand

"She wanted to be inputted into the game as an AI but we stopped her. So, we created an opportunity for her to talk to you. Through the quest items that you were handed to begin the quest about the Diversion Arch Castle, you would have to finish the quest to be able to unlock the 'feature' that allows her to interact with those that 'saved' or 'obtained' her...." the Doctor said as Shino clutched the hand of Izumi tighter

"Can I...speak to her?" Shino asked and the Doctor's eyes widened but he smiled

"There's an Amusphere in the next room. Log in to ALO there. You should be able to talk to her since you've finished the quest required to talk to Asukara." the Doctor said as Asuna put a hand on Shino's shoulder. Shino looked at Asuna and then hugged her tightly

"Thank you, Asuna..."

Asuna smiles for her friend

"No problem, Shinonon."

Then, Shino bolted out towards the next room.

***

Using her ability to create a path to the place where she found Asukara's body, Sinon found herself in front of Asukara.

"Time to talk to me, sis." Sinon said, placing a hand on the apparatus, thinking it would open...which it did.

The liquid drained and Asukara' naked body spilled out. Using an unused cape in her inventory, she wrapped Asukara in it and led her to the side of the room. She placed her on the wall and sat herself beside her, hugging her tight.

Suddenly, the clone of Sinon stirred and her eyes opened "What...?"

"Awake already, Asukara?"

Asukara couldn't see who was it that held her as her eyes were still adjusting to the dim lighting of the room that she was kept in "Eh? Is that you, Doc? Why's your voice feminine?" Sinon fought the urge to laugh. Instead, she hugged the girl tighter and ruffled her black hair..

"Look at me, Asukara."

Doing as she was told, Asukara's eyes widened "W...Who are...?"

"Who do you think am I, Izumi?"

Asukara's eyes widened even more

"Shi...no-nee...chan?!?!?!"

"Bingo!"

Asukara tried to stand up, to try and wake herself up if it was a dream. But, her feet, still wet of the clear liquid from her containment unit earlier, made her slip. Sinon caught her just in time, she laughed a little at the girl's clumsiness "Take it easy, Asukara. You've been sleeping for a long time. Even if this IS a virtual world, your body still needs to adjust a little..." Sinon reminded her

The small girl blushed but nodded as they both sat back down on the floor. Then, silence reigned...for a long while. Asukara, soon, decided to break it, wanting to know why and how...

"How did you find me, Sinon-nee-chan?"

"I heard you wanted to be made into an AI to just wait for me here. But they didn't allow it. They just made a quest made specifically for me. For me find you. When I did finished, I researched your name that was on the apparatus you were in and when your hospital popped up, I'm here!" Sinon told her excitedly.

"...you could've just left me as is...why did you try to find me...?"

"Oi, oi. You were the one looking for me now that I was the one looking for you, you dislike it? Make up your mind, Izumi."

The sound of her name coming out from her sibling figure made Asukara stop

"Do you...believe me if I said I'm not sure if we're really related? Just us having the same last name attracted me to your exploits in the virtual world...?" Asukara asked and Sinon sighed with a contented smile

"Who cares if we're not actually related? I mean, Asuna cared for Yuuki even if they weren't related. Heck, Asuna, Leafa, Silica, Liz, Yui, Agil, Klein and Kirito cared for me even if I weren't related to them. Couldn't it be the same for both of us, Izumi?" Sinon asked which made tears come out from Asukara's eyes.

She launched herself onto Sinon's hold and hug her.

"Thank you, Sinon-nee!!"

Sinon smiled "Of course, you're welcome, Asukara..."

***

"Hey, Sinon, your child sure is lively isn't she?" Leafa teased and Sinon raised an eyebrow "What do you...?"

"I mean, she's already atop a huge cliff, Sinon-san..." Yui pointed to Asukara who was bouncing everywhere atop the cliff "I just turn my back on her for one moment and she's somewhere dangerous again!" Sinon said as she flew towards Asukara. The others enjoying how Sinon was looking after Asukara with worry.

A few days has passed since Sinon's first encounter face-to-face with Asukara. She discovered that she could be taken out of the apparatus for sometime but was recommended to be put back in it by sundown. She introduced Asukara to her friends and they've been all looking after her. They discovered that Asukara is a Salamander like Klein but she chose to hang out a lot with Sinon, despite her being a Cat Sith.

Well, Sinon became the one who took on the role of overprotective mother...

"Asuka! What're you doing up here?!"

"Calm, calm, _mama._ I'll just fly back down with Asuna-san..." Asukara said, flying down and landing next to Yui and Asuna who were both eating food prepared by Asuna. Yui handed Asukara a riceball which she thanked the AI fairy.

Sinon shook her head and flew to join them...

***

"But still, Sinon..." Kirito suddenly said which made Sinon look up from wiping Asukara's cheeks filled with rice "What is it, Kirito?" Sinon asked

"You really are a doting mother, are you not?" he teased which made her blush

"Of course she is! Sinon-nee-chan just became my mother! She would visit me everyday in the hospital and when you guys don't hang out with us, she and I would talk in my room all day!" she resorted to calling the castle where she was found her room

"Ohhh? Shinonon-kaa-san!" Asuna teased and everyone laughed. Sinon blushed

"Come on, guys! Stop it!!"

**The End**

**Author's Note:**

> I love Sinon.
> 
> That's it.
> 
> I want her to be my sister.
> 
> Well, I did make it that way.
> 
> VA REVIEW:  
> Shino Asada CV: Miyuki Sawashiro (same with Mordred from Fate and Elizabeth from Persona 3)
> 
> ORIGINALLY POSTED IN WATTPAD: IzumiAsada647


End file.
